C程序设计教程与实验(吉顺如 陶恂)实验10答案

#include #include void main() { FILE *fp1; char ch[80]; int i,j; fp1=fopen(\"D:\\\\datal.dat\ for(i=1;i<=4;i++) {gets(ch); j=0; while(ch[j]!='\\0') {fputc(ch[j],fp1); j++; } fputc('\\n',fp1); } fclose(fp1); }

Sy10-2

#include #include #include void main() { int x[10],i,k; FILE *fp2; srand((unsigned)time(NULL)); for(i=0;i<10;i++) x[i]=rand(); fp2=fopen(\"data2.dat\ if(fp2==NULL) { printf(\"Open error \\n\");exit(0); } for(k=0;k<10;k++) fwrite(&x[k],sizeof(int),1,fp2); fclose(fp2); }

Sy10-4

#include

#include void main() {FILE *fp; int i=0;

char *str[]={\"visual C++\ if((fp=fopen(\"file10_4.txt\ {printf(\"%s不能打开!\\n\ exit(1); }

while(i<4) { fprintf(fp,\"%s\ i++; }

fclose(fp); }

Sy10-5

#include #include main() { FILE *fp; char c; int i=0,no=0,line=0; if((fp=fopen(\"text.txt\ { printf(\"can`t open this file.\\n\"); exit(0); } printf(\"please input a string.\\n\"); while((c=getchar())!=EOF) { if(c>='a'&&c<='z') c=c-32; fputc(c,fp); } fclose(fp); if((fp=fopen(\"text.txt\ { printf(\"can`t open this file.\\n\"); exit(0); } while(!feof(fp)) {

c=fgetc(fp); no++; if(c=='\\n') line++; } printf(\"line=%d character_no=%d\\n\ fclose(fp); }

Sy10-6

#include #include #include void main() { FILE *fp6; int i=0; char str[][20]={\"visual C++\ char s[20]; if((fp6=fopen(\"file10_6.dat\ { printf(\"%s不能打开!\\n\ exit(1); } while(i<4) { fwrite(str[i],sizeof(str[i]),1,fp6); i++; } fclose(fp6); if((fp6=fopen(\"file10_6.dat\ { printf(\"%s不能打开!\\n\ exit(1); } fread(s,sizeof(s),1,fp6); while(!feof(fp6)) { printf(\"%s\\n\ fread(s,sizeof(s),1,fp6); } fclose(fp6); }

Sy10-7

#include #include main() { FILE *fp7; int a,m=0,n=0; if((fp7=fopen(\"number.dat\ { printf(\"open error\\n\"); exit(0); } while(!feof(fp7)) { fscanf(fp7,\"%d \ if(a>0) m+=a; else n+=a; } printf(\"正整数之和为%d,负整数之和为%d\\n\ fclose(fp7); }

Sy10-9

#include #include #include struct student { char num[20]; char name[10]; float s1,s2,s3,ave; }stu[5],*p=stu; main() { FILE *fp9; int i; for(i=0;i<5;i++,p++) { fflush(stdin); printf(\"\\n请输入第%d位学生的学号:\ gets(p->num); printf(\"请输入第%d位学生的姓名:\ gets(p->name);

}

printf(\"请输入第%d位学生的三门课成绩:\ scanf(\"%f%f%f\->s1,&p->s2,&p->s3); p->ave=(p->s1+p->s2+p->s3)/3; }

p=stu;

if((fp9=fopen(\"stud.dat\ { printf(\"open error\\n\"); exit(0); }

for(i=0;i<5;i++,p++) fprintf(fp9,\"%s %s %.2f %.2f %.2f %.2f\\n\->num,p->name,p->s1,p->s2,p->s3,p->ave); fclose(fp9);